434 FEEDING FARM ANIMALS 



horns respectively. They are classified as light, medium 

 and heavy. The cost of producing 100 pounds of butter fat 

 with these respective groups was $17.93, $17.79 an d $17.42. 



The following facts are noteworthy : ( I ) The 25 Jer- 

 sey cows entered in the competition at the Lousiana Pur- 

 chase Exposition in St. Louis, 1904, were considerably 

 larger in size than the average of the breed. They weighed 

 911.2 pounds on an average at the commencement of the 

 test and 983 pounds at its close. These cows were used 

 in a test of which economic production was a prominent 

 factor. (2) The cows that have proved the world's record 

 makers are considerably above the average in size. (3) The 

 same is true of a majority of the cows entered in the vari- 

 ous advanced registry associations. 



While the difference in relative profit from large and 

 small cows respectively is not large, it unquestionably be- 

 longs to those of large size. It is probably the outcome of 

 the relation between size and the relative amount of the 

 food maintenance required. This in mature animals is 

 even more than one half the entire ration. Probably more 

 than nine-tenths of the heat generated by the food goes 

 to supply the loss through radiation, perspiration and respi- 

 ration. The loss through radiation is greater relatively in 

 the small than in the large animal, owing to the relatively 

 larger body surfaces in the former. 



But aside from relative milk production, there are 

 some reasons why breeders should aim to produce relatively 

 large rather than small cows for the breed. These include 

 the following: (i) Good constitution and stamina are 

 more frequently associated with well developed animals, in- 

 cluding cows, than with those less well developed. (2) Uni- 

 formity in size should be the aim of the breeder as an 

 evidence of good and skilful breeding, and the standard 

 thus set should favor at least average size for the breed, as 

 a guaranty of the absence of degeneracy. (3) Animals of full 

 size, or rather more, take the market more readily than those 

 under size, whether sold for the dairy or the shambles. 



